Fuel and air control



Nov. 24, 1931. I w. w. WILLIAMS i i 1,833,273

A FUEL AND. AIR CONTROL I Filed Jan. 17, 1930 2 sheets-sheet r1 ATTORNEY Nov. 24, 1931. w. w. WILLIAMS 1,833,273

FUEL AND AIR CONTROL Filed Jan. 17, 1930 2 sheets-sheet 2 z llllll i INVENTOR Wm ER m WML/4ms ORNEY Patented Nov. 24, 1931 UNITED s'm'rasv APara 4NT OFFICE f WALTER W. WILLIAMS, OF BLOOMINGTON, ILLINOIS, ASSIGNOR. TO WILLIAMS OIL-0# MATTO HEATING ILLINOIS FUEL In CONTROL OORPORATION, or BLOOIIINGTON, ILLINOIS, A CORPORATION or Original application led J'ne 18, 1928, Serial No. 288,314. Divided and this application med J'alfuary 17,

` 1930. Serial No. 421,875.

' This invention relates to improvements in liquid fuel burning devices for domestic urposes and more particularly to fuel an a1r controls Vfor the operation thereof and is a division of my prior (zo-pending application, Seria-l N o. 286,314 filed June 18, 1928.

Certain types of ers sup ly the li uid fuel by gravity to a pot or com ustion c amber adapted to be inserted within the fire box of the furnace or heater of a house heating system and in which air for combustion is supplied to the combustion chamber vfrom a casing surrounding the side and bottom of the combustion chamber and having an air intake leading therefrom, the air for combustion entering through apertures arranged in the walls of the combustion chamber and the amount. of air passing therethrough regulated by a damper in the air intake. In burners of this typethe flame is either initially ignited by the throwing into the combustion chamber of a piace'of burning paper or match or by a gas pilot 'and v the combustion Occurs as the incoming fuel splreads over the base of the combustion amber and vaporizes and mixes with the air coming in throu h the sides of the combustion chamber. T e height above the bottom of the combustion chamber at which said vapors burn varies with the amount of oil and air supplied so that when' a small amount of oil is supplied, and a small amount of air is provided the flame occurs nearthe bottom of the chamber and upon increasing the supplies of both oil and air in proper proportions, the vapors burnl at or labout the top t of the combustion chamber.

- It is an object of this invention to a device of this character which wi matically burn with-a low flame when first ignited and provide an electric thermostatic i control to be placed ina room 'of the dwelling where the temperature is desired to be maintained at a certain degree which control, when the temperature falls below the desired degrec, will not only operate a valve to increase' the amount of oil supplied to the burner and provide a Athermostatic controlA actuated by the temperature of the bottom ofthe combustion chamber to increase the supply of air domestic liquid fuel heatnism actuated thereby arranged on t provide lf autof I i automatically as the oil supply is increased and which will' act conversely when the tem' v perature of the room exceeds that of the desired amount whereby both the oil and air supply will be^reduced to the minimum under which the fiame will continue to burn. In explaining the embodiments of this invention reference is made to the accompanying sheets of drawings illustratin the preferred. forms, it bein understoo that the invention is not restricted tothe particular burner shown nor to the-particular type of float valve oil supply and that minor detail changes may be made in the various controls without departing from the scope of the in-/ va-tionwith parts broken away of another' embodiment of thisV invention showing the application of the thermostatic or bi-metallic control upon the underside of the combustion chamber and thel damper operatin mechae side of the` draft pipe. v

Figure 5 is -a to planview of the thermo--V static or bi-metalllc control, as shown in Figure 4.

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. invention is not restricted to the articular application thereof, as shown.. he li uid lfuel burner comprises a cylindrical com us- The cylindrical casing 3 joins the /top o the side walls of the combustion chamber 1 which side walls are provided with a pluralit ofy small open' r arranged in tiers par leltothe botto'mo the chamber. Afan lowerL 6 is mounted-within the fany housing 5 and is preferably operated by the motor shaft of a small motor 7 supportedr thereabove. "A float operated oil valve chamber 8 is preferably mountedon the draft pitpe 4 v' adjacentthe motor 7 which is connecte center' of the the pipe 9 to an oil tank or otherl source of *liquidV fuel, not shown, throu h which the li uid fuelis sup lied to the oat chamber.

The underside o the float chamber is'conL nectedto a fuel dischar pipe 10 which extends centrall' of the raft pi Wer side of the ttom 2 of the combustion chamber 1 andat whichpoint is provided with a dischar the combustion chamber. e float valve chamber8 isa commercial article and form no ypart of thisinvention, it being suicient for theunderstanding of the operation of the device to state that this chamber is provided with two dischargevalves 11 and 12. The

valve 11 is'manually set to supply suilicient oil to the combustion chamber to allow combustion to occur therein with the flame adjacent the bottom of said chamber and the valve 12, while normally remaining closed, ma be manually or otherwise lifted to admit 'su cient oil to pass into the oil pipe 10 to provide additional `fuel to the combustion chamber, which, whenv sufficient air ismixed with the vapors thereof as .to cause the llame to burn in a plane adjacent the top of the combustion chamber. z

The electricity employed to operateA the motor 7 is taken from the commercial line and passes throu h the house switch S b wayof wire 13 to t e motor and back throng wire 14 to the house switch, A transformer 15 is shown` mounted upon the motor which is connected in,` parallel with thecommercial circuit 13 'and 1'4. The secondary circuit passesfrom one terminal of the transformer through wire 16 to the boiler control B and from the boiler control by the way of wire 17 to a' room thermostat T and thence by way .of wire 18 to an electric heating coil 19 arranged about a strip of bi-metallic metal 2O secured' at one end to the top of the float 4 to thel opening intoV valve chamber 8 and having the other free q end in engagement with the hi 12 and so arranged that when t e bai-metallic strip is heated b the heating element 19 it will raise the-va vef12 and admit. additional oil to the combustion chamber. From the heating coil 19 the secondary circuit passes throu hl wire 21 back'to lthe other terminal'of t e transformerl. The boiler control is a ycommercial articlevr and varies in type` with the `type of heating system to `vwhich the burner is applied. If the heating system isl a hot water s stem the boiler control stementers into t e water within the boiler and .is responsive to the temperature thereof. If a steam system, the stem of the boiler controlY enters the 'boiler above the lire valve water line and is responsive to the steam] pressure therein, and if hot air or vapor system, the control is 4responsive to the teinperature thereof. The control as -shownfincludes a' mercury tube switch ,which isnormally in closed vposition andwhen the condtions within the boiler approach the danger line the control resl nds thereto and operates the mercury tu t e circuit therethrough. The room thermostat is also a commercial article and'v forms no vpart of this invention. As illustrated,

the roomA thermostat comprises a mercury j tube switch and includes mechanism r n-y siveto the temperature of the room inw ich the thermostat is located to close the cirswitch to break l cuit when the temperature descends to a oer y tain degree and tobreak the circuit when the temperature rises to a certain degree.

In this type of burner mechanism it isseen that the fan-blower is continuously-operat'l i 1025,

as flong as'the house switch S remains c and the amount of air supplied through the draft ipe 4, circular casing 3 andl through the ho esf in the side walls of the combustion s chamber 1 is suilicient to maintain a high fire condition provided suilicient li uid fuel is supplied to the combustion cham r. It is therefore necessary when the 1amount of oil supplied tothe combustion` chamber isde creased to Acorrespondinglydecrease theA air y supply. To accomplish this a damper 22 is mounted within the draft pipe 4 of such a size that when in closed position only suicient air will pass therebyfroin the fan blower to the combustion chamber to mix the fuel vapors to provide a low fire where theflame occurs adacent the bottom of the combustion chamber. l is dam er 22 is provided with a pivotal member w ich extends beyond the side of the V draft pipe 4 and is bent adjacent itsend-tov 121sv A U-shaped stripof bi-metallic:`

nessus of the bottom of the combustion chamber which pie passes out through the side of the cylin rical casing 3 and extends parallel to the draft pipe for a short distance. The free end of the bi-.metallic strip 24 1s attached to a rod 26 which passes through the ipe and is adapted to engage a pivoted` ever 27, preferably mounted in abracket carried upon the extremity of the pipe 25. The

free end of this lever is connected to the free produce suicient heat upon the bottom of the combustion chamber 2 to cause the thermostatic member 24 to expand and thereby through rod 26, lever 27, and rod 28, will cause the dam -r 22 to assume the position shown, andthe urner will operate indefinitely this way 'as long as -fuel 1s supplied to it. The

boiler control B is shown closed while the room thermostat T is shown in the open position. When the temperature of the room in which the thermostat is located drops below the desired degree, the thermostat will close the secondary circuit from the transformer whereupon the heat coil 19 will cause the strip of bi-metal 20 to move upward and open the fire valve 12 whereupon additional oil h 'gill Hood the bottom of the combustion chamber reducing the temperature thereof and causing the thermostatic member 24 to cool and contract whereby thedam r 22 will be opened'wliicli will supply suiclent air to the combustion chamber to cause the flame to burn adjacent the top of the chamber whereby the bottom of the combustion chamber will remain suicien'tl cool to cause the U-shaped strip of bi-metal ic metal 24 to remain contracted. The burner will then continue to burn with a high fire until the room thermostat breaks the secondary circuit whereupon the heating element 19 will cool and the bimetallic strip of metal 2O will close the high .lire valve, cuttin down the supply of oil to the combustion c amber, and as the flame descenda toward the bottom, the heatthereof will expand the U-shaped strip 24 and cause the damper to close and the burner will burn with the low fire as long as oil is supplied to it until the'room thermostat again calls for heat.

Figures 4 and 5 illustrate a modified type of combustion chamber controlled thermostatic mechanism. In this case a strip ofbimetallic metal l29 secured at its center to a block mounted in a housin 30 which housing is secured to the undersi e oi the bottom of the combustion chamber 2, is shown. The free ends of the strip of bi-metallicmetal are then curled about themselves and toward each other, as shown in Figure 5, and their ner as t e L J-shapedstri metal 24. Asy illustrated in Figure 4, the

free Aends engaged 4in a loop. in the A'26| whereby this particular type oithermostaticV control o rates the rod 26in the same inanrod 24 en es a lever 3l`which1s'mo`unted on the en yo a central pivoted member. ofthe damper 22 and normally, by means of springs 32, holds the damper in open position when the coils of the coiled.

` Figure 6 illustrates another forin of damI er control mechanism. In this case a straig t strip of bi-metallic metal 33 'is secured` atone thermostatic metal 29 are side of the fuel inlet to the combustion .cham

ber at one end by bracket 33"*,mountediipon the underside of thebottom 2 of the combustion chamber V1 which also supports the'p'ipe '25. The strip 33 normally departs f ij'omfthes. bottom 2` from its fixed end until the.f' f1fee` end is at a distance therefrom. The 'free end is connected by a link .34 to a bell crank lever 35 ivotally supported in a bracket 36 exof bi-nietallic ten ing from the underside of thebottom2 ofthe combustion chamber with the other arm-l connected tothe rod 426 whereby, when the fuel is ignited and burnsinthe combustion chamber adjacent the bottom, the heatthereof'will -causepthe thermostatic strip to` curl.,

upward until its movement is limited by contact to the bottom 2. This movement will be damper as herein efore described. Figure 7 illustrates a modified, form Aof damper operating mechanism which also includes a motor switch.. f When this typeof mechanism isv em loyed'fthe motoronly operateswhen the fp `transmitted through the rod 26 to close the V26 passes from the underside of the combus-l tion chamber. Any desired type of'combustion chamber responsive thermostat can be employed to operate the rod 26. The free end uel is burning with a high `fire' within the combustion chamber.` This of the rod 26 is shown in engagementv with a lever 38 mounted at its upper end upon the ,ri

casing 37 and with its lower end connected by a rod-39 to the operating lever 23 of the damper 22. The lever 38 mounts the mercur tube switch 40 in the manner shown, whi

mercury tube switch is in the motor circuit.

When the burner isburning with a low fire the combustion chamber responsive thermostatic mechanism will cause thel rod 26 to move in the direction of the combustion chamber tilting the lever 38 about its ivot.

so that the circuit will be broken throug the mercury tube switch to the motor and at the lli same time the dam er `32 will be closed,

whereby it is seen t at the motor remains idle while the burner is burning with a low lire. When the room thermostat calls for y l i .10887819.73

.heatan additional oil is supplied to the combustion chamber and the bottom of the chaml ber will be flooded cooling the chamber suffciently toallow the thermostatic member v pito contract whereby the rod 26 causes the .`lever 38 to tilt in the position shown in Fi ure 7. This closes the. motor circuit throug the mercury tube 40 and'at the same time' opens the damper 22 whereby the additional 1 .air required for the hi h fire will be immediately su plied throug the operation of the motor an the motor will continue to operate as long as the room thermostat callsl for heat. p When the room thermostat breaks the secondary circuit, the supply of oil is reduced and the fire in the burner assumes the lower osition increasin the temperature of the x ttom of the com ustion chamber, the thermostatic member 29 will expand and cause an the rod-26 to move to the right whereby the leverv38 will be tilted and cause the mercury tube switch to break the motor circuit at the same time closing the damper 22. This arrangement is more economical than the ones 2 5 heretofore described inasmuch as the motor is only o rating when a high lire is desired.

What claim is: K 'A domestic liquid fuel heating device comrising in combination, a burner including a 80 iquid'fuel receptacle, an air suppl means therefor including a conduit, a fue supply means includin two controls therefor, one of which contro s permits fuel to flow to said receptacle at a minimum rate, aroom thermo- 35 stat adapted to actuate theother of said conv trols to permit fuel to flow to said rece tacle at amaximum rate, a thermostat adjacent the receptacle and operative invaccordance with a minimum supply of fuel to decrease f 4o, the air supply, and operative in accordance with a maximum supply of fuel to increase the air suppl `l WALTER W. WILLIAMS. 

